Two players each think of a word. They say them out loud simultaneously, using the verbal setup of "one, two, three" to synchronize the utterances of the chosen words. Each player reviews the two words and then tries to think of a word that connects the two. The players simultaneously say "one, two, three," and then their new chosen words. The process is repeated until both players say the same word.
For example, the players might start with "green" and "hamburger." In the next round one player might say "lettuce" and the other "pickle." In the third round, both players might say "vegetable," and end the game. A word used by either player may not be used as the chosen word in any subsequent round.
See also 1-2-many
1-2-3 was introduced by Rubrick (nommed Rastelli at the time)